Exothermic heating unit



Sept 2i 1930. J. H. DEPPELER v EXOTHERMIC HEATING UNIT Filed Nov. 2,1926 I N VEN TOR.

ATTORNEY.

Patented Septn 2, 193() Qumran STATES PATENT OFFICE JoHN n. nnrrrmnn, orWEI-BHAWKEN, New sesam AssIGNon To THE HEAT RE- SEARCH AND snavronoonroRArrioN, or WILMiNGToN, DELAWARE, A CORPORA- TION OF DELAWAREnxorirmuvrrc HEATING UNIT Application filed November 2, 1926. Serial No.145,867.

The invention relates to heating units operated by the reaction of anexothermic mixments is a good conductor of heat, so that the high degreeof heat developed by the exothermic reaction may 3e readily transmittedthrough the heat conducting portion of the container or casing withoutmaterially impairing any part o f the container, wherei by the developedheat may be applied to the material to be treated therewith withoutreleasing the products of the reaction other than the heat from thecontainer.V

The invention is illustrated in one of its adaptations in theaccompanying drawing, in which:

The ligure is a sectional elevation of a container adapted to receive achargel ofv exothermic mixture. Y

Among the various applications of heat produced by the reaction ofexothermic mixtures, such as thermit and the like, are 1nf eluded theloosening or disintegration of ice masses, the melting of ice or otherobstructions in pipes o conduits, pumps, hydrants, or the lilre, but, inall such applications, 1t has been customary to release the highly A"heated products of the exothermic reaction from a container in which thereaction is carried out, usually by melting or destroying all or partofthe container by the heat generated. lt has been found, however, that,in many instances, it is desirable to utilize the heat of the exothermicreaction, without liberatingthe permanent elements of the reaction inthe form of molten metal and slag, as, for example, in forming holes inice masses to i thermal bombs, as explained in No. l,562,l37, datedNovember 17, 1925, in remevin g meltable or fusible obstruc* tions inpipes, pumps, hydrants and the like, and in many other relations inwhich the local application of a relatively high degree of heat is fourdnecessary or desirable.

rlhe present iin/'cation is designed to provide a container for anexothermic mixture, of such character that the enclosing walls orelements will not be materially impaired by the heat of the reaction ofthe exothermic mixture, but will nevertheless deliver the developed heatat the place or location desired. This result may be obtained byproviding a metallic container having walls of such character andconstruction that they will not be materially impaired by the heat ofthe reaction, at least one of said walls or enclosing elements beingmade of a highly conductive metal, which will 'transmit and localizepractically all ofthe heat of the reaction at the desired point.

In the application of the invention t0 relatively small units, such aswould be required in thawing out frozen hydrants and meltingobstructions in pipes and conduits, the container may conveniently takethe form ofan enclosing shell of iron or steel, the walls of which arethick enough to withstand the heat of reaction, so that the entirereaction may be completed and all of the heat expended by conductionthrough the walls of the container, without permitting any of tienormally solid reaction products, such as molten metal and slag, toescape. tainer would generally be used but once, as the highly vmoltenmetal and slag would probably be either fused with or adhere to theinterior walls of the container, so that it would be more expensive toremove these reaction products than it would be to provide a newcontainer.

'In another mode of application of the invention, as, for example, informing holes in ice masses, or similar operations, itis both desirableand economical to construct a receptacle or container for the exothermiccharge that will deliver the heat of the reaction in a definitedirection, as, for example, through the bottom of the container, toeffect a rapidmelting of the ice or other vbody with which the containeris in contact, to form the desired hole. A typical example of such acontainer is illustrated in the drawing, in which l represents an outercup-like shell of relatively thin iron or steel, which is lined with afilling of heat insulating material 2 of any,y suitable character.Within the lined shell l is a second shell or casing comprising atubularsection 6, preferably of iron or steel,

In such cases, the con- IUU having a top closure 7 which may be of likemetal, the members 1 and 6 being connected by a metallic ring 3,preferably welded to each of said sections. The open end of thecomposite container, as thus constructed, is closed by a plate Ll,preferably of a metal which is a good conductor of heat, such as copper,said plate being removably secured to the container by means of bolts 5passing through holes formed adjacent the peripheral edge of the plateand engaging tapped openings in the ring 3, the top face of the plateforming a substantially tight joint with the lover rim of the tubularsection 6. The interior walls or enclosing elements 6 and 7 and theclosure 4 of the container are of sufficient thickness to withstand theheat of reaction of an exothermic mixture within the container, so that,if means are provided for removing the residual products of the reactionin the form of metal and slag, it will be entirely practicable to usethe container repeatedly. This result is obtained by providin a cup lO,preferably made of iron or steel,

` which is removably inscrtable within the container and is supported bythe bottom 4, when the latter is secured in place. The charge of theeXothermic mixture is supplied to the container and, when said chargehas been ignited and the reaction is completed, all of the residualproducts will be held within the cup l0 and may be removed from thecontainer by iirst removing the bottom plate 4. VVh'en the reaction istaking place, however,

, I the heat generated thereby will be conducted by the metallic wallsof the cup 10, as well as the inner walls 6 of the container, to thehighly conduct-ive metal bottom 4L, so that practically all of the heatof the reaction will be delivered by the bottom l directly to thematerial or article to be heated, and, in case the apparatus is used forforming holes in ice. the concentration of the heat at the area ofcontact between the bottom of the container and the ice will form a holeof the desired depth with great rapidity and certainty. In such cases,however, it is desirable to provide the container with a suitable vent,for although, theoretically, the exothermic reaction produces nointernal pressure, it is almost inevitable that sufficient moisture iscarried by the eXothermic mixture or by the container to develop steam,which might disrupt the container, unless it be 'permitted to escape. Totake care of these conditions, therefore, it is preferable to providethe container with avent pipe 9, which is of a length sutlicient toextend to the top of the hole in the melting ice, or other material, toprevent the entrance of water into the container and said vent pipe maybe conveniently attached to the container by threading it into the ringor coupling 3.

It will be understood that the particular form and structure of theheating unit, as4 illustrated, is merely exemplary and may be varied tomeet special conditions, without departing from the invention, which isintended to provide a container capable of delivering all of the heat ofthe reaction to the material to be acted upon by such heat, withoutpermitting the residual-elements of the eXothermic reaction to escapefrom the container.

lVhat I claim is:

l. A heating device for melting ice masses comprising a shell includingside, top and bottom walls of a character to withstand the heat from thereaction of exothermically reactive materials, the bottom wall being agood conductor of heat and removably secured to the side wall, aninsulating sheath enclosing the top and side walls, and a removablerefractory cup in the bottom of the shell adapted to receive and retainthe residual products of the reaction.

2. A heating device for melting ice masses comprising a shell includingside, top and bottom walls of a character to withstand the heat from thereaction of exothermically reactive materials, the bottom wall being agood conductor of heat and removably secured to the side wall, aninsulating sheath enclosing the top and side walls, a removablerefractory cup in the bottom of the shell adapted to receive and retainthe residual products of the reaction1 and a vent tube connected to thetop of the shell.

In testimony whereof I affix my signature.

JOHN H. DEPPELER.

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